摘要 |
A shank adapter for rock drilling machines includes an elongate generally cylindrical body including first and second end portions, the first end portion having a thread for connecting the adapter to a drill string, the second end portion including a torque transfer structure for transferring torque between the adapter and the drill string. The body includes an internal longitudinally extending flushing channel terminating in an exit orifice disposed in the first end portion, and a side-flushing hole extending laterally from an envelope surface of the body to the flushing channel. The side-flushing hole is of non-circular cross-section. A radially external bordering edge of the side-flushing hole has a convex curvature as viewed from the envelope surface outside of the hole and is generally elongated to define opposite ends which are more sharply curved than other portions of the bordering edge. |